THE BRAZEN seizure of Iraq's second-largest city, Mosul, and subsequent military advance by insurgents operating under the banner of the Islamic State in Iraq and Syria (ISIS) has detonated a renewed civil war with the frightening potential of intensifying sectarian conflict throughout the Middle East.

The Guardian reports that Iran has sent Qasem Soleimani, the commander of an elite division of the Revolutionary Guard, along with other advisers and 2,000 troops, with the hope of shoring up the Shia-dominated central government in Baghdad. On Iraq's northern border, Turkey is contemplating action in defense of its personnel kidnapped by ISIS from a consulate in Mosul.

And now, Barack Obama has ominously declared, "I have asked my national security team to arrange a number of options. I will be reviewing those options in the days ahead." On Sunday, Defense Secretary Chuck Hagel ordered the aircraft carrier USS George H.W. Bush to move into the Persian Gulf off Iraq's coast, along with support ships armed with guided missiles. The U.S. could launch strikes from sea or air against ISIS targets.

ISIS fighters on the streets in Mosul

The corporate media, which for the most part has ignored the escalating conflict in Iraq since the withdrawal of U.S. troops at the end of 2011, was bewildered by ISIS's victory. The new consensus among commentators is that the new crisis was caused by the vacuum left by the U.S. pullout.

In reality, it is not the absence of U.S. troops, but the 2003 invasion and subsequent occupation that is to blame for the sectarian civil war that threatens to reach a new level of barbarism in Iraq. Further American intervention of any kind would only make an already disastrous situation even worse.

WHAT IS the background to the current situation?

ISIS is the offshoot of al-Qaeda in Iraq, which emerged during the U.S. occupation in 2006. It is led by Abu Bakr al-Baghdadi. ISIS looks to an extreme version of Sunni Muslim fundamentalism that regards Shia Muslims as heretics. Thus, ISIS claims that it has executed hundreds of Iraqi soldiers from the Shia-dominated army, who were taken prisoner during its offensive.

With about 6,000 fighters drawn mainly from Iraq, but also other countries around the region and the world, ISIS aims to establish a new caliphate in Syria and Iraq. Its reactionary politics and brutal practices in both Syria and Iraq are so extreme that even al-Qaeda expelled the group from its network.

ISIS has established a base in the cities of eastern Syria during the uprising and civil war in that country. It sent around 1,200 fighters to take the northern city of Mosul, with a population of about 2 million people.

A garrison of 30,000 Iraqi Army soldiers put up no resistance to this tiny force. Instead, apparently on orders from their commanders, they abandoned the city, leaving behind an enormous cache of military equipment, from Humvees to helicopters and machine guns, which ISIS now wields. Once in control of the city, the insurgents raided the city's banks, taking nearly half a billion dollars in assets.

Half a million people have fled Mosul in terror, according to the International Organization for Migration, searching for refuge in other cities of the Kurdish-controlled North. But most of Mosul's population was happy to see the Iraqi Army depart. The majority look on it as an occupying Shia force.

As one Mosul resident, Ali Aziz, told the Guardian:

I feel we have been liberated from an awful nightmare that was suffocating us for 11 years. The army and the police never stopped arresting, detaining and killing people, let alone the bribes they were taking from detainees' families. Me and my neighbors are waiting for the news that the other six Sunni provinces have fallen into the hands of the ISIS fighters, to declare our Sunni region, like the three provinces in Kurdistan.

ISIS has mainly targeted representatives of the central state and has yet to impose its harsh version of Islamic law in the conquered territory, instead trying to curry favor with the population. It remains to be seen how the population will respond if and when ISIS imposes bans on smoking and drinking, restricts women's rights and conducts summary executions of infidels and those who disobey its edicts.

After the quick conquest of Mosul, the insurgents sent forces to seize Tikrit, Saddam Hussein's hometown, and a couple other cities. They hope to add these to Falluja and Ramadi, which have been under the control of Sunni forces for months, to form an incipient Sunni-controlled section of Iraq.

Ominously, ISIS spokespeople have declared that they will attack Baghdad, along with Shia religious sites in Samara and the Shia holy cities of Najaf and Karbala. They have called for the indiscriminate murder of Shia that stand in their path.

CONTRARY TO the conventional wisdom of the ignorant corporate media, ISIS's victory did not come out of nowhere. The dynamics that enabled its fights to seize Mosul and other cities have been developing for several years.

Over the last year and a half, the Sunni population of Iraq has been conducting a mass campaign of mostly nonviolent resistance against Iraq's central government. This is the result of Prime Minister Nuri al-Maliki increasingly transforming the government into a Shia one. Maliki has refused to integrate the Sunni Awakening Councils into the Army; maintained the anti-Baathist law, implemented after the U.S. invasion for use against remnants of Saddam Hussein's regime, to target all Sunni political forces; and went after Sunni politicians and leaders with accusations that they support terrorism.

The Sunni population across Iraq responded by fighting for their rights with mass demonstrations and sit-ins throughout 2013. At one point, important Shia leaders like Moqtada al-Sadr, who have their own grievances against the Maliki regime, expressed solidarity with these Sunni protests and threatened to organize demonstrations of their own. But this hopeful moment of solidarity proved fleeting, just as similar developments have in the past.

Maliki responded to the wave of protests--what some called the Iraqi Spring--with a brutal campaign of repression. He turned to tactics learned from the U.S. occupation--neighborhoods sweeps, mass arrests and torture. Thus, the overwhelming majority of the Sunni population was driven into desperate opposition by the actions of the Maliki government.

With the repression intensifying, forces among Sunnis like ISIS, which opposed the regime on sectarian grounds, gained increasing prominence and leadership because of their willingness to confront security forces. Maliki in turn used the threat of ISIS's sectarianism to convince Sadr to stage demonstrations in support of the Iraqi state. This further consolidated Maliki's hold on an increasingly exclusive Shia autocracy, defended by a Shia-led and -staffed army.

Since then, ISIS has forged closer ties with former leaders of the Baath Party that ran the military and state under Saddam, as well as local tribal leaders. Forces in this alliance seized control of Falluja and Ramadi at the end of last year, and now, with financial support from sectarian Sunni elites outside Iraq, this alliance has now added Mosul and Tikrit to its growing empire.

All this has precipitated a profound crisis for the central Iraqi state, which has been exposed as a Shia institution with no support from the Sunni population--and less and less from the Kurdish people and their regional government in the country's North. Maliki's army of 200,000 soldiers has proven itself to be sectarian and incompetent, despite the $25 billion that the U.S. spent on building it up.

Iraq stands on the edge of a new civil war that could be worse than the last one, which raged from 2005 through 2008, with an average of 3,000 civilians being killed every month.

ISIS and its allies now control Mosul, which is particularly significant because of its oil wealth, along with several other predominantly Sunni cities. They have major backing from regional elites, and they are now armed to the teeth with confiscated American weapons.

The Kurdish rulers, who sat out the last civil war between Iraq's Arab Sunnis and Shia, reacted to ISIS's seizure of Mosul by expanding their own territory. They used the security vacuum left by the dissipating Iraqi Army to order their Peshmerga militia to take over Kirkuk, another key oil center. Kurdish elites still promise to collaborate with Maliki, but they have always had their eyes on becoming an independent state.

Maliki's central state is thus facing an existential crisis. It has lost legitimacy and lost the ability to enforce its rule. Out of desperation, Maliki has turned to the Shia establishment led by Grand Ayatollah Ali Sistani, and sometimes-opponents like Sadr and the Islamic Supreme Council of Iraq (ISCI) to mobilize volunteers to rebuild their Madhi Army and the Badr Brigades--Shia militias that slaughtered Sunnis in the last civil war. Thousands of Shia have joined the reforming organization to fight alongside the Iraqi Army.

This time, the conflict between the rulers of Iraq's three main communities--Kurds, Shia and Sunni--could be even more apocalyptic. In the past, the ruling classes of each community stepped back from outright partition because they want a piece of the oil profits controlled by the central state. Now the centrifugal dynamics seem to be overshadowing the motives for maintaining a united nation state.

The Shia control the central state, its Army and the Shia militias. The Sunnis are attempting to construct their own state to challenge Maliki's. And the Kurds, who rule over a booming oil economy through their Peshmerga militia are, unlike in the past, now engaged in the conflict over the possible partition of Iraq.

THE PRINCIPAL cause of this crisis is three decades of U.S. imperial policy that culminated in Bush's 2003 invasion.

Before the first Gulf War in 1991, barbaric sanctions in the 1990s and Bush's invasion and occupation, Iraq was a developing capitalist society, with a standard of living on par with Greece. Now, after the latest U.S. war led to an estimated 1 million Iraqi deaths and a civil war that displaced 4 million people, Iraq stands on the precipice of disintegration.

Sectarianism did exist before the 2003 invasion and occupation. Saddam Hussein's regime principally benefited the Sunni elite, with repression meted out against both Kurds and Shia. But there was nothing like the systematic sectarian violence that exists now. And there was no al-Qaeda, despite the Bush administration lie--used, like the fabrication about weapons of mass destruction, to justify invading--that Hussein was collaborating with the terrorist network.

The U.S. occupation precipitated a fractured resistance of Sunnis and Shia. Washington alienated the Sunni population with its de-Baathification law that led to Sunnis disproportionately losing their jobs. Bush lost the Shia population because he extended the occupation to prevent allies of Iran, like Maliki, ISCI and Sadr, from winning control of the country through elections. In short order, the U.S. could only count on Kurds in the North to remain loyal to the occupation project.

When the U.S. finally allowed elections in post-invasion Iraq, it adopted the Lebanese model that apportions power by sect and ethnicity. This enraged the Shia, the largest of the three main groups in Iraq, which saw this as a blow to their ability to rule. Yet the Sunnis realized that even with apportionment under the U.S. plan, they would lose out. As a result, Sunnis organized a guerilla struggle--while the Shia led by Moqtada al-Sadr's Mahdi Army staged mass protests against the occupation.

For a moment, it seemed as if the fractured resistance would unite across the Shia-Sunni divide against the occupation.

But the U.S. was successful in implementing its divide-and-rule strategy, exploiting a new development in the resistance that proved to be its Achilles heel--the unprecedented emergence of al-Qaeda in Iraq, the group that would become ISIS, which targeted not only the U.S. occupation, but the Shia people and their religious sites.

Faced with these attacks, Shia leaders like Sadr and ISCI built their own militias to enforce order amid the chaos of the occupation--and also to defend themselves against al-Qaeda sectarianism. The U.S. encouraged these militias to join the police and security forces to put down the Sunni population. It thus drove a wedge between the resistance forces--and detonated the civil war that raged from 2006 to 2008.

American propagandists celebrated Bush's infamous "surge" of combat troops as the reason that the civil war came to a close. In reality, the civil war largely ended before the larger U.S. presence arrived--because the Shia had won the conflict.

The Sunni tribal leaders called off their fight after suffering defeat at the hands of the Shia militia. Instead, they sought to curry favor with the U.S. by targeting al-Qaeda in Iraq. Washington then put these Sunni forces on the payroll, with the promise that the Shia-dominated state would be pressured to make concessions allowing for their participation.

But by that time, the rulers of each community saw politics as a zero-sum game. Maliki was never going to agree to incorporate the Sunnis into his regime. He, like his allies among the Shia religious parties, was aiming for a Shia state. The last thing they wanted was real power-sharing. Meanwhile, despite their criticisms of Maliki, Bush and then Barack Obama continued to support the central state, dominated by Shia leaders--further alienating the Sunni population.

In short, Bush and then Obama helped spread the bacillus of sectarianism throughout the region to counter-act their defeat in Iraq.

When Iraq was invaded in 2003, Bush had planned this to be a stepping stone to regime changes in Syria and Iran, with pro-American regimes installed across the region to ensure U.S. hegemony over the Middle East and its oil resources. With that accomplished, the U.S. would be in a position to dominate its rivals among the world's major powers--especially China, which is dependent on Middle Eastern oil.

But that project failed in Iraq. Iran could now add Iraq's Shia government to its list of allies in the region, stretching from Hezbollah in Lebanon to Assad's regime in Syria and Hamas in Palestine. Ultimately, Iran emerged as the unintended victor of the Iraq War.

The U.S.--and its regional allies, especially Saudi Arabia's fundamentalist regime--now tilted again, spreading fears of a "Shia Crescent" that would challenge the regional balance of power. Thus, the U.S. directly facilitated the increasingly state-backed sectarianism that is ripping through the Middle East.

MEANWHILE, THE response of the Arab autocracies to the Arab Spring rebellions was also to intensify sectarianism.

The rebellions in Tunisia and Egypt toppled U.S. allies in early 2011, inspiring the Arab masses in all corners of the Middle East to rise up against their autocratic rulers and their neoliberal economic policies. They demanded not only democratization, but also economic equality.

For its part, the U.S. attempted to manipulate the revolt for its own ends. It used the rebellion in Libya to get rid of an untrustworthy ally, Muammar al-Qaddafi. But Barack Obama and his administration turned a blind eye when their Sunni extremist ally Saudi Arabia used savage repression to crush the predominantly Shia uprising in Bahrain. And Obama did nothing to stop Saudi Arabia from backing Sunni sectarian forces among the developing Syrian revolution against dictator Bashar al-Assad.

Assad's brutal regime is a sectarian one; he has amassed power in the hands of the rulers of the Alawite sect, an offshoot of Shia Islam. The revolt against the dictatorship began as a popular uprising that united people across sectarian divisions. Assad responded by doing everything in his power to crush the revolt militarily--and divide it along sectarian lines. He welcomed Shia forces from Iran and Hezbollah of Lebanon to help confront the predominantly Sunni revolt.

But Assad also freed the worst Sunni extremists from his jails. These forces joined the military resistance to Assad, but began targeting the Alawite and Christian population--just as Assad hoped, having judged that that the threat posed by these Sunni sectarian militias would solidify his base in the Alawite and Christian minority. Saudi Arabia and Qatar backed the worst of these Sunni extremist forces, including ISIS.

Assad--preferring to target the more secular and united revolutionary forces in the West--avoided targeting ISIS, which rebuilt itself in Eastern Syria. Spared repression, ISIS established a base that could easily unite with the Sunni areas of Western Iraq.

In Iraq, Maliki's sectarian repression of the nonviolent movement drove formerly rival Sunni forces into an alliance against the central state. ISIS, former Baathists and tribal leaders united in an increasingly military resistance to Maliki. In general, the Sunni population came to see the extremists as the lesser evil to Maliki's sectarian repression, even though most Sunnis do not subscribe to ISIS's extreme fundamentalism.

Faced with this alliance, Maliki pleaded for the U.S. to provide his regime with more arms. While Obama grumbled about Maliki's refusal to integrate Sunni forces into the regime, he went ahead and agreed to step up the flow of weapons and supplies, including new attack helicopters and patrol boats. The U.S. thus contributed to the further militarization of the sectarian conflict spawned by its previous occupation.

But Obama has been reluctant to intervene directly in Iraq. He declined Maliki's request earlier this year to conduct air strikes against ISIS targets. The U.S. empire has suffered a relative decline since it was forced to withdraw from the country at the end of 2011. Obama has been attempting to refocus his imperial project on containing the rise of China in Asia and the re-emergence of Russia as a power in Eastern Europe and Central Asia.

The U.S., however, can't afford to lose control of the Middle East to the sectarian instability it engendered. But any new intervention it conducts will only make things worse. If Obama backs Maliki with military action, it will drive the Sunni population further into the arms of ISIS and its allies.

It is hard at this point to imagine any political reconciliation between the rulers of Iraq's three main communities. The U.S. has no solution to the sectarian violence it has unleashed and supported in Iraq and throughout the region.

THE OBAMA administration doesn't have a coherent strategy in the Middle East. Its neoconservative opponents are wrong in their claims that Obama lacks the stomach for war--on the contrary, he has amply demonstrated his disregard for human life with the escalating program of drone strikes around the region.

Rather, Obama's reluctance to fight is a direct result of the relative decline of U.S. power since its defeat in Iraq and the looming failure in Afghanistan--which are compounded on the economic plane by the Great Recession of 2008 and subsequent global slump.

Unable to impose its will on the Middle East, the U.S. has instead had to rely on wildly contradictory alliances to stabilize an order threatened by revolt from below and sectarian division from above.

Thus, Washington is in a de facto alliance with Iran--which it bitterly denounces as an enemy--to defend the Shia regime in Iraq. At the same time, it maintains its historic alliance with Saudi Arabia, which is supporting the Sunni militias to topple Maliki in Iraq and Iran's ally Assad in Syria.

None of the other states in the region nor any other imperial power has any solution to the metastasizing crisis. Iran is bolstering Assad and Maliki. Turkey supports the downfall of Assad, yet fears the collapse of the Iraqi Shia state, because that would open space for the Kurds to declare an independent state, thereby enflaming Turkey's own Kurdish minority to rise up and fight for their right to a homeland.

Saudi Arabia and Qatar are fueling the most extreme Sunni militias throughout the region. And Israel's brutal occupation of Palestine is stirring resistance among Palestinians and their allies through the international boycott, divestment and sanctions campaign.

U.S. imperialism's attempt to lock the Middle East under its hegemony through the war in Iraq has failed. Its manipulation of sectarianism in an attempt to divide and conquer the Iraqi resistance has generalized the divide between Shia and Sunni states throughout the region. Iraq is coming apart at the seams--and its disintegration threatens to engulf the entire region in military conflict.

The hope amid this horrific situation is the revolutionary process triggered by the Arab Spring.

At its height, the rising of the people--students, workers and peasants--attempted to bridge the sectarian divisions of the region. For example, in Egypt, revolutionaries called for unity between Muslims and Coptic Christians. Even in Iraq, where the sectarian virus was deliberately set loose by the U.S., Sunnis and Shia were, at some points, close to a tactical unity in their fractured resistance to the occupation.

One difficulty is the weakness of the revolutionary left, which could promote common class interests among workers across the sectarian divisions, and build struggles on this basis. During the current counter-revolutionary phase of the process, the cost of this weakness is on full display--most obviously in Egypt, where the military's harsh repression has taken a toll.

But the order presided over by regional elites and the world's major powers alike has no answer to the yearning of ordinary people across the Middle East for peace and economic justice--and these grievances are therefore bound to emerge again in some form against the lack of democracy, neoliberalism and American imperialism.

In the meanwhile, the left everywhere must be absolutely clear that neither the U.S. nor any other regional power or rival imperialism has a positive solution to the spreading sectarian conflict. They are all capitalist states in competition with one another for regional and international dominance. In the U.S., we must rebuild an anti-imperialist current to oppose all intervention by the U.S. or any other state.

As Iraq's descent into chaos and conflict proves once again, the U.S. and its imperial rivals are part of the problem, not the solution.

Material on this Web site is licensed by SocialistWorker.org, under a Creative Commons (by-nc-nd 3.0) license, except for articles that are republished with permission. Readers are welcome to share and use material belonging to this site for non-commercial purposes, as long as they are attributed to the author and SocialistWorker.org.